1. Field of Invention
The present invention relates to a package structure. More particularly, the present invention relates to a package structure compatible with a cooling system.
2. Description of Related Art
In an information-explosion world, ICs are widely used in the daily life, including entertainment, education, transportation and households. The design of the electrical products becomes more complex and high-speed and multi-function chips are developed. As the integration of ICs keeps increasing and the layout of the high-speed semiconductor devices becomes dense, more heat is generated by the semiconductor device per unit area in a certain period. Thus, it is important for the design of semiconductor devices to consider the heat dissipation issue, in order to prevent damages to the electronic devices or the chips.
FIG. 1 is a cross-sectional view of a prior art wiring package structure. A chip 140 is arranged on a carrier 100 having a first surface 102 and a second surface 104. A die pad 110 and a plurality of pads 120 are disposed on the first surface 102, while a plurality of ball pads 130 are disposed on the second surface 104. A plurality of bonding pads 146 is disposed on an active surface 142 of the chip 140, and a back surface 144 of the chip 140 is attached to the die pad 110 through silver paste 150. Each bonding pad 146 is electrically connected to one of the pads 120 through a gold wire 160, thus electrically connecting the chip 140 with the carrier 100.
A mold compound 170 covers the chip 140, the gold wires 160 and the first surface 102 of the carrier 100 for protecting the chip 140 and the gold wires 160. A heat dissipation plate 180, for dissipating heat from the operation of the chip 140, is disposed on the outer surface of the mold compound 170.
In theory, the heat dissipation plate 180 can help dissipate heat generated from the operation of the chip 140 into the exterior of the mold compound. However, as discussed above, as the package becomes minimized and chip per unit area generates more heat in a certain period, it is unlikely to rely on the heat dissipation plate done to dissipate all the heat. Therefore, the un-dissipated heat can cause serious damages to the electronic devices on the active surface of the chip. In fact, inefficient heat dissipation can cause quite a few problems, including: (1) the un-dissipated heat results in higher resistance for the current of the electronic device, thus influencing the signal transmission (signal delay) or giving rise to error signals; and (2) the un-dissipated heat deteriorate the performance of the electronic device, even shortening the life of the electronic device on the chip.